Colorado Income Tax Calculator 2026
Colorado taxes income at a single flat 4.4% rate for 2026 — estimate yours below.
Colorado's flat 4.4% income tax, explained
Colorado (CO) taxes income at a single flat 4.4% rate rather than graduated brackets, so — unlike the federal system — every dollar of Colorado taxable income is taxed at the same rate. That makes the state calculation simple, but it is separate from federal income tax and from Colorado sales tax.
What to know about Colorado tax
- Colorado applies a single flat income-tax rate to federal taxable income, making the state calculation unusually simple.
- The state sales-tax base is only 2.9% — the lowest non-zero state rate — but Colorado allows aggressive local add-ons, so combined rates are often high.
- Colorado has periodically issued taxpayer refunds under its TABOR revenue-limit rule.
Frequently Asked Questions
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Calculate →Disclaimer
This calculator provides estimates for informational and educational purposes only. SmartTaxCalcs does not provide tax advice. Your actual tax liability may differ based on your specific situation, recent law changes, and circumstances not modeled here (e.g., AMT, NIIT, special credits). We strongly recommend consulting a qualified tax professional (CPA, Enrolled Agent, or tax attorney) before filing or making financial decisions.
Data source: IRS Revenue Procedure / state Departments of Revenue. Last data update: May 19, 2026.